Flexible hinges



March 31, 1959 T, HINDLE 2,879,580

v v FLEXIBLE HINGES Filed March 9, 1956 4 Sheets-Sheet 1 Mar/la raw/9 y @M/M @M March 31, 1959 Filed March 9, 1956 T. H INDLE FLEXIBLE HINGES 4 sheets-sheet 2 x March 3l, 1959 T. HINDLE FLEXIBLE HINGES 4 Sheets-Sheet 3 Filed March 9, 1956 T HINDLE FLEXIBLE HINGES March 31, 1959 Flled March 9 1956 2,879,580` FLEXIBLE HINGES Thomas Hindle, Blackburn, England Application March 9, 1956, Serial No. 570,555

Claims priority, application Great Britain December 7, 1956 12 Claims. (Cl. 28-78) This invention relates to flexible hinges such as are employed for belts, such as conveyor belts, power 'transmisnited States Patent O sion belts, or, in particulan'fo'r paper-makers dryer felts.

In the art of paper-making on a Fourdrinier papermachine, after the paper libres have been formed into a coherent sheet at the wet end of the machine, the sheet is delivered to the dry end for movement over steam-heated cylinders, whereby the paper is consolidated and dried. The sheet is held in intimate contact with the hot cylinders by means of dryer felts which are frequently of great length and width andare extremely costly. Such felts are ordinarily manufactured entirely of cotton, or of av combination of cotton and asbestos, or of a combination of cotton and synthetic libres or filaments, or of a combination of cotton, asbestos and synthetic libres or laments, or entirely of synthetic bres. Most dryer felts are woven flat and the ends joined to form an endless structure after the felt has been positioned over the drying cylinders and felt rolls of that section of the paper-machine which the felt is to clothe. It is obviously desirable to make the joint which is known in the paper-making art as a seam both secure and ilern'ble, and one which may be quickly made to save time in fitting.

Numerous methods are employed to join the ends of the dryer felts. The ends may be over-lapped and sewn, riveted or glued together. Alternatively, the ends may be brought together in butt joint and secured by means of a strip of felt or strong webbing sewn, riveted or glued to the underside of both ends of the felt 'at the joint, the actual ends of vthe felt being otherwise unattached. One of the `most successful and expeditious methods of joining together the ends of a belt, including a paper-makers dryer felt, is a form of flexible hinge known as a clipper belt-fastener, vconsisting of a plurality of regularly Vspaced wire clip elements 'adaptedvat one end to be clinched under mechanical pressure in the manner of a wire staple into the belt, and having hinge-like loops at the other end adapted to be interdigitated while a flexible pintle member to act as a hinge pin is threaded through them thus forming a flexible hinge. If such clips are applied directly to the 'ends `of the felt itself, the hinged joint so formed is too insecure as the ends 'of the felt are raw or cut and do not have sutiicient strength to withstand the tension applied during the normal running life of the felt on the paper-machine, so that the clips detach themselves from the end ofthe felt. For this reason, the metal clips have been "rst attached 'to one selvedge of strong webbing three to four inches wide, and a strip of this webbing with the Yclipper loops in position, has been securely attached by sewing to the 'underside of, and across each end of the felt. To ensure A'that the clips remain securely attached tothe webbing and that the completed seam remains intact during the normal service life of the felt, a multi-ply webbing, preferably of four layers, is required. There :is therefore produced a considerable step against the underside of the lfelt by 'the edge of such webbing away from'th'e hinge pin. Now, a

drying section of a paper-making machine contains a. number of rollers, known in the art as felt rolls, of relatively small diameter with which the underside of the continuously moving felt cornes into contact. Each time the seam passes over a felt roll, there is avsharp impact of the leading edge of the webbing on the felt roll'as the seam meets the roll, and a hammering effect is produced on a transverse strip of the felt immediately following the trailing edge of the webbing as the seam leaves the roll. These step eiects are mechanically destructive and may occur many times per minute, the recurrence being dependent of course upon the speed of the paper-making machine and the number of felt rolls contained .in the drying section over which the seam has to pass. As a result of such step effect, the leading edge of the leading webbing and a transverse strip of the felt itself immediately following the trailing webbing becomes more severely and more rapidly disintegrated than the body of the felt.

The webbing for the clips has to be of substantial thickness, usually 3 to 4 ply, for sufficient strength to carry the clips. rlhe problem of the step effect aforesaid has been partly met by using two thinner superimposed pieces of webbing of different widths so as to divide the one original step into two smaller steps, one selvedge of each strip being coincident for receiving the clips. Nevertheless, it has been found in practicethat the use of two strips of thinner webbing of different width, although an improvement on the use of a single thicker strip of webbing, is not wholly satisfactory. The leading edges of both the wider and narrower strips of the leading webbing are more rapidly worn than the rest of the webbing, and the steps between the two strips of trailing webbing and the wider vstrip of trailing webbing and the felt are still too great to avoid premature degradation of a transverse strip of the wider webhing and a transverse strip of the felt immediately following the wider webbing.

The principal object of this invention is to provide an improved means for jointing the ends of a dryer felt and includes an improved form of webbing which is firm enough and strong enough to hold securely the hinge clips and which is relatively free from the step effects 'of the webbing used heretofore in the construction of such flexible hinge joints.

According to the invention, means for securing a ilexible hinge to the ends `of a belt, such as a paper-makers dryer felt, comprises a exible hinge-clip receiving member of homogeneous character adapted to be attached transversely to the ends of the felt and having one edge adapted to receive and hold the clips, the member tapering in thickness towards the other edge to reduce the step elfect thereat.

According to a preferred embodiment of the present invention, the member is in the form of webbing to which the clips are attached in the construction of a exible hinge joint for use on a paper-makers felt, and consists of a narrow woven fabric tapered in thickness so that the selvedge which receives the Wire clips Vis of three or more layers and the other selvedge which faces towards the body of the felt is of one layer only.

The invention as applied to the so-called seam of paper-makers dryer felts is now described in greater detail with reference to the accompanying drawings where- 1n:

Figure 1 is a vertical section longitudinally of a felt at the clip-type vhinge seam, showing the known use of webbing of uniform weft-'ways cross-section;

Figure 2 is a vertical section longitudinally of ak felt at the clip-type hinge seam showing the known use at Figure 3 is a plan view of a portion of a paper-makers dryer felt at the clip-type hinge seam showing one example of a novel tapered thickness webbing with which the clips are engaged and made in accordance with the present invention;

Figure 4 is a vertical section longitudinally of a felt at the clip-type hinge seam showing the novel tapered thickness webbing of Fig. 3 in weft-ways cross-section;

Figure 5 shows an alternative method of stitching the novel tapered webbing to the ends of the felt;

Figure 6 is a diagrammatic illustration of one Weave structure of tapered webbing made in accordance with the present invention and shown as a formal section through a straight warp.

A flexible hinged seam as illustrated in Fig. l is made by inserting wire clips 24 and 26 at regularly spaced intervals along one selvedge of each of two strips 32 and 34 of four-layer homogeneously woven webbing. One strip of such webbing with the clips attached is stitched to the underside of each end of the felt 10 in such a manner that when the two sets of clips are engaged (interdigitated) to provide a continuous passage through the eyes, the ends of the felt form a closelybutted joint 12 just beyond the longer clinching parts 28 of one set of clips 26. vThe flexible hinge seam is completed by the introduction of a flexible pintle member 42 through the interleaved eyes of the clips.

With a flexible hinge joint seam so constructed, when the felt is run on the paper machine in the direction indicated by the arrow A, excessive mechanical degradation occurs along the leading edge 36 of the webbing 32 and across the whole width of the felt at 14, immediately behind the trailing edge 38 of the webbing 34. This excessive degradation occurs, as previously explained, because of the depth of the step at 36 and 38 between the underside of the felt and the strips of the webbing.

A exible hinge seam as illustrated in Fig. 2 is made by stitching together two superimposed pieces of webbing 52 and 52', of different widths, the selvedges 62 thereof being in registration. Similar superimposed pieces of webbing 54 and 54' are stitched together with registering selvedges 64, and wire hinge clips 24 and 26 are inserted at regularly spaced intervals along each of the registering selvedges 62 and 64. The webbing with the clips attached is stitched to the underside of each end of the felt 10 and the joint is completed in the same manner as previously described by the insertion of a exible hinge pin. When a felt with a exible hinge seam so constructed is run on a paper machine in the direction indicated by the arrow A, in spite of the fact that there are two steps between the felt and the outer layer of webbing, these steps will cause premature degradation at the leading webbing selvedges 56 and 56', to the trailing webbing 54 at that portion 58 immediately following webbing S4', and across the whole width of the felt at that portion 16 immediately following the trailing edge 58' of the webbing 54.

The exible hinge seam illustrated in Figs. 3, 4 and 5 is made according to one example of the invention with tapered thickness webbing. One construction of such webbing, embodying the present invention, is shown and described, solely by way of example and without intended limitation, in Fig. 6 and is such that as shown in these figures, one piece of webbing 72 is so constructed that, for approximately one-sixth of its width from one selvedge it has a single layer section 88a, this being followed by a two-layer section 86a, then a three-layer section 84a, and the remainder 82 of the webbing, representing approximately one-half of the total width, has a four-layer construction. The other piece of webbing 74 has a similar tapered cross-section in which sections 92, 94a, 96a and 98a are of four, three, two and one layer constructions, respectively. Wire hinge clips 24 and 26 are inserted at regularly spaced intervals along each of the selvedges of the four-layer sections 82 and 92 of the strips of webbing 72 and 74. The two strips of webbing with the clips attached are stitched to the underside of each end of the felt 10 and the exible hinge seam is completed in a manner similar to that described earlier above. As illustrated in Fig. 4 the hinge seam is made with the steps of the webbing facing outwards, whereas as illustrated in Fig. 5, the hinge seam is made with the steps of the webbing facing inwards, i.e. towards the underside of the felt. Both methods of construction are satisfactory.

When 'a felt with a flexible hinge seam with tapered thickness webbing in accordance with the present invention is incorporated is run on a paper-making machine in the direction indicated by the arrow A, the steps from the felt to the thickest portions of the strips of webbing are less sharply defined and relatively so shallow that localised degradation to lany part of either strip of webbing or to that part of the felt immediately following extension 98a of the trailing webbing 98 is substantially reduced or eliminated. Furthermore, because the hinge clips have been inserted into the selvedges of the four-layer portions of the webbing, they are as securely held as if the whole of the webbing were of uniform four-layer construction.

One example of weave for a suitable tapered thickness webbing for a flexible hinge seam according to the present invention is illustrated in Fig. 6 in which the weave structure is shown as a formal section through a straight warp. The webbing is 3 inches wide and consists of four layers, respectively a first layer 88 comprises a section 88a approximately one-half inch wide, measured inwardly from one selvage edge, the part 88a being a single layer fabric comprising the parallel warps W; a second layer 86 having la section 84a which underlies a part of the layer 88 to form therewith a two-layer fabric approximately one-half inch wide wherein the warps W1, W2 are in superposed planes; a third layer 84 having a section 84a which underlies parts of the layers 88 and 86 to form therewith a three-layer fabric approximately one-half inch wide wherein the warps W3, W4 and W5 are superposed planes; and nally, a fourth layer 82 which underlies parts of layers 88, 86 and 84 to provide a four-layer fabric approximately one and one-half inches wide wherein the warps W6, W, W8 and W9 are in supperposed planes. The construction is of plain weave, the layers being bound together by means of binder warp threads 89, land the picking order of the weft threads is chosen so as to produce a firm, smooth main selvedge to the four-layer section 82. Since the warps run lengthwise of the seam and provide the anchorage for the spring clips, the warps must necessarily be heavy and this means that the wefts must be sharply bent in interweaving with the warps. However, the wefts which extend transversely of the webbing (and thus lengthwise of the felt) must collectively carry the load imposed by the pull of the felt and thus it is essential that each individual layer of the multi-ply fabric consists, in major part, of wefts interwoven with the warps of a single layer only, in order that the fabric may provide as nearly as possible maximum resistance to transverse elongation.

The weave structure as shown in Fig. 6 is such that in the upper and lower warp planes certain wefts, for instance those indicated at K, extend without deflection from the respective warp planes. The major portions at least of the respective Warp planes and the binder warps 89 are so located that those stitching wefts m, n, x, y, etc. which pass from one warp plane to the next at the shoulders (where each thicker portion of the fabric joins the next adjacent thinner portion) extend diagonally so that the angle at each step, where one ply is offset from the next, is substantially less than a right angle. It will be evident that, at the shoulder where a thicker portion joins the adjacent thinner portion, the warps and wefts are so interwoven as to provide a nonraveling quasi-selvage devoid of loose yarn ends. Inspection of Fig. 6, which diagrammatically depicts the result of a single weaving cycle, shows ,that eight picks of lling or weft are introduced during each such cycle. The pick which begins at the point designated A and whichextends transversely to the right, as seen in Fig. 6, is hereinafter referred to as the first pick. Study of Fig. 6 shows that this rst pick interweaves with all of the warps .of the upper or top layer of warps and also at regular intervals interweaves with binder warps S9.

The second pick, which commences at the point indicated by the letter B, and which is woven in while the shuttle travels to the left, interweave-with all of the warps of the fabric section 88a; but, at a point y, this second pick leaves the top layer and begins to interweave with warps of the second layer and continues to interweave with all of the warps of the second layer which are comprised in the fabric section 86a and at intervals also interweaves with binding warps 89 located between the iirst and second layers. Then, at the point x, the second pick leaves the second layer of warps and begins to interweave with warps of the third layer, continuing to interweave with all of the warps of the third layer comprised in the fabric section 84a and, at recurrent intervals also interweaves with binder warps 89 located between the seco-nd and third layers; then, at the point n this second pick leaves the warps of the third layer and begins to interweave with warps of the fourth or bottom layer, continuing to interweave with the warps of the fourth layer and at intervals also intervening with binder warps 89 located between the third and fourth layers.

The third pick which commences at the point C and, traveling toward the right, interweaves with all of'the warps of the third layer to the left of the fabric section 84a and at regular intervals interweaves with binder warps 89 between the layers 3 Iand 4.

The fourth pick, which commences at the point D, travels toward the left and interweaves with all of the warps of the third layer which are to the left of the fabric section 84a and, at recurrent intervals, also interweaves with binder warps 89 located between the second and third layers.

The fifth pick, which kcommences at the point E and travels toward the right, interweaves with all of -the warps of the second layer which are to the left of the fabric section 86a and, at recurrent intervals, interweaves with binder warps S9 which are between the second and third layers.

The sixth pick, which begins at the point F and travels toward the left, interweaves with all of the warps of the second layer which are to the left of the fabric section 86a and, at recurrent intervals, interweaves also with binder warps 89 located between the first and second layers.

The seventh pick, which begins at the point G and travels toward the right, interweaves with all of the warps of the top layer which are to the left of fabric section 38a, but, does not interweave with any of the binder warps 89.

The eighth pick, which begins at the point H and travels toward the right, interweaves with all of the warps of the second layer within the fabric section 86a, then leaves the warps of the second layer at the point x and interweaves with all of the warps of the third layer within the fabric section 84a, and then leaves the third layer, `at the point n, and interweaves with all of the warps of the fourth layer which are to the left of the fabric section 84a, but nowhere interweaves with any of the binder warps 89.

Thus, while the fabric might supercially appear to be a true multi-ply fabric, at least in those portions which are to the left of the fabric section 88a, it is, in reality, a multi-layer fabric (rather than a multi-ply fabric) to the left of the section 88a, since the constituent layers are not independent plies merely held together by stitching warps or wefts as is customary `in multi-ply fabrics, but is actually a unitary` structure which cannot be separated into independent self-contained plies by -the severance of any of its constituent yarns since certain, at least, of the wefts are essential elements of each of the several layers. To express this difference between the unitary fabric structure herein disclosed anda multi-ply fabric of customary type, the several layers of the present fabric are herein referred to as quasi-plies. In weaving webbing in ac'- cordance with this example, there is total of 420 warp yarns each of 6s/2 (cotton counts) spun Terylene and 54 weft yarns per inch, each of 6s/5 spun Terylenef This figure of the drawing is, of course, diagrammatic and shows fewer than the full num-ber of warp threads and in consequence the dimensional proportions of width above given have had to be distorted in the drawing -in order to show the weave.

It is to be 'understood that the invention is not limited to the above example. The webbing lmay be woven of cotton yarns, of synthetic "yarns, of a combination of cotton yarns and synthetic yarns, of yarns vproduced from blends of cotton and synthetic fibers, or of yarns produced from blends of different Vsynthetic fibres. In certain cases, a three-layer webbing, tapered to one layer, is suflicient, whereas in other cases, a veor six-layer webbing, tapered in one-layer steps to one layer, is more satisfactory. Neither 'the total width of the webbing nor the widths of the various steps are critical and both may be varied without departing from the scope of the invention.

Whilst the tapered webbing as heretofore described is illustrated for use in'rnaking the hinge 'seam at the ends of paper-makers dryer felts, it is obvious that it has characteristics which make it Valuable for use in joining the ends of .other endless belts, such as conveyor belts or power-transmitting belts.

It will be appreciated that oneparticular clip-type hinge construction for use with the novel tapered webbing has been described by way of example. Many modifications to the type of hinge may be made without departing from the scope of the invention -of the use of a tapered webbing in the construction of a clip-type exible hinge seam.

I claim:

1. Means for securing a flexible hinge to the ends of a belt such as a papermakers dryer-felt thereby to form a seam, said means comprising a multi-ply woven fabric having selvages at its opposite edges and consisting of layers of warp elements of different widths and in overlapping arrangement producing zones of a progressively different number of plies in thickness, characterized in that the -warp elements in each layer lare interwoven with wefts `in such a way thata portion, at least, of each layer forms a separate ply free from adjacent plies, while certain warps .of each layer are bound at spaced intervals to warps of each adjacent layer by certain of the wefts, the fabric comprising four plies at one selvage and a single ply at its opposite selvage.

2. Means for securing a flexible hinge to theends of a belt such as a papermakers dryer-felt thereby to form a seam, said means comprising a multi-ply woven fabric having selvages at its opposite edges and consisting of layers of warp elements of different widths and in overlapping arrangement producing zones of a progressively different number of plies in thickness, characterized in that the warp elements in each layer are interwoven with wefts in such a way that a portion, at least, of each layer forms a separate ply free from adjacent plies, while certain warps of each layer are bound at spaced intervals to warps of each adjacent layer by certain of the wefts, the number of plies decreasing progressively from one selvage to the other, and at the edge of each narrower ply, wefts from the narrower ply extend diagonally toward and are interwoven with warps of the next adjacent ply.

3. Means for securing a exible hinge to the ends of a belt such as a paper-makers' dryer-felt comprising a strip of multi-ply woven fabric of the order of three and onehalf inches in width and having selvages at its opposite edges, one selvage being relatively thicker than the other, the fabric comprising a plurality of warp planes within each of which warps are interwoven with wefts to form a ply or layer, certain wefts from each warp plane being stitched at intervals to wefts of the next adjacent plane by binder warps, the exposed ply at one face of the fabric being of greater width than the next adjacent ply and the latter being of greater width than the next ply and so on, the thicker selvage of the fabric providing a secure anchorage for the exible hinge.

4. A hingesecuring member according to claim 3 wherein each of the warp plane layers comprises portions of single ply fabric in which the warps and wefts are interwoven in a plain weave, said portions being free from adjacent plies.

5. Means for securing a iiexible hinge to the ends of a belt such as a paper-makers dryer-felt thereby to provide a connection between said ends, said means comprising 'a strip of multi-ply woven fabric having selvage edges, one selvage edge being ,substantially thicker than the other, said fabric comprising a plurality of warp planes in each of which wefts are interwoven with warps to form a ply or layer, certain wefts diverging at intervals from one warp plane to the next and being stitched to wefts in the next adjacent warp plane, said warp planes, beginning at one face of the fabric, progressively diminishing in width, each warp plane comprising a portion at least in which the wefts are interwoven only with the warps in said plane to form a single ply fabric.

6. Means for securing a exible hinge to the ends of a belt according to claim wherein certain of those wefts which diverge from the warp plane at one face of the fabric pass in successive steps to and are interwoven with the warps of the warp plane 'at the opposite face of the fabric.

7. For use in anchoring an element of a flexible hinge to one end of a belt, such as a papermakers dryer felt, a woven textile fabric having parallel selvages and wherein warps extend substantially parallel to the selvages, the fabric being thicker adjacent to one selvage than to the other, and progressively diminishing step-by-step, in thickness, from the thicker selvage toward the thinner selvage, with a shoulder, parallel to said selvages, at the junction of each thicker portion with the next adjacent thinner portion, the fabric being of unitary construction wherein warps and wefts are so interwoven as to form a non-raveling quasi-selvage at each of said shoulders.

8. A woven textile fabric, according to claim 7, wherein each of the thicker portions comprises warps disposed in parallel planes, with stitching wefts uniting warps in adjacent planes, certain of the stitching wefts being exposed at each of said shoulders to form, with adjacent warps, the non-raveling quasi-selvages.

9. A unitary Woven fabric for use in anchoring a metallic hinge element to one end of a belt, such as a papermakers dryer felt, said fabric having parallel selvage edges and having portions widthwise thereof which are .of different thicknesses, said portions decreasing in thickness progressively step-by-step from one selvage toward the other, the fabric consisting of warp yarns and weft yarns so interwoven that at the junction of each thicker part with the next adjacent thinner part there is a sloping shoulder wherein the warps and wefts are interlocked to form a quasi-selvage.

10. For use in anchoring an element of a flexible hinge to one end of a belt such as a papermakers dryer felt, a multi-layer woven fabric having parallel selvages and comprising a plurality of quasi-plies, successive plies progressively diminishing in width, one selvage of the fabric being thicker than the other selvage and comprising 'all the quasi-plies, each quasi-ply comprising warps parallel to the selvages of the fabric interwoven with wefts, and binder warps interposed between each pair of adjacent plies, at least one of the weft picks which is introduced during each cycle being interwoven with warps of each of said quasi-plies and with at least one binder warp located intermediate the edges of each respective quasi-ply.

11. A multi-layer fabric, according to claim l0, wherein, in each quasi-ply, one pick of weft is interwoven with all of the warps of said ply and at regular recurrent intervals with binder warps located between said quasi-ply and the next adjacent quasi-ply.

12. A multi-layer fabric, according to claim 10, wherein at least one of the weft picks, which is introduced during each cycle, is interwoven with warps adjacent to that edge of each quasi-ply, which is remote from the aforesaid thick selvage, to form a quasi-selvage parallel to said thick selvage.

References Cited in the le of this patent UNITED STATES PATENTS 708,630 Fanta Sept. 9, 1902 943,557 Marti Dec. 14, 1909 977,357 Zeglen Nov. 29, 1910 1,986,490 Wilson Jan. l, 1935 2,025,275 Diamond Dec. 24, 1935 2,084,490 Hooper June 22, 1937 2,629,909 Hall Mar. 3, 1953 2,672,168 Walters 1 Mar. 16, 1954 

